报告时间：2019年5月7日周二上午9:30-10:30
地点：北辰校区材料楼517
报告题目: High-Resolution Visualization of the Redox Activity of Li2O2 in Non-Aqueous Media: Conformal Layer VS. Toroid Structure
报告内容: A strong relationship between the surface structure and the redox activity of the Li2O2 is visualized directly using a scanning electrochemical cell microscopy, byemploying a dual-barrel nanopipette containing a unique gel polymer electrolyte. These measurements reveal considerable local heterogeneity with significantly enhanced electrochemical activity at toroidal Li2O2 structures when compared to the conformal layer that is usually formed on the cathode of Li–O2 batteries.
Dr. Pei San E，女，英国华威大学制造工程系研究员。2017年毕业于英国华威大学，获得理学博士学位。从2011年至今，先后在Fuji Electric公司担任工程师、在英国剑桥大学任职副研究员、以及在英国华威大学担任研究员等职务。迄今获得过马来西亚国家科研创新奖、英国创新展金奖、英国最佳创新奖、马来西亚可持续发展创新奖等奖项。目前主要从事于基础电化学、纳米电化学、生物电化学、气体传感器以及锂离子电池等方面的研究工作，且在国际著名期刊包括ACS Applied Mater. Inter.,ElectrochimicaActa, J. Phys. Chem. C, PCCP等国际期刊上发表SCI论文多篇，并20余次被邀请在国际重要会议做学术报告。
报告时间：2019年5月7日周二上午10:30-11:30
地点：北辰校区材料楼517
报告题目: Non-Aqueous Electrodeposition of Functional Materials
报告内容: Thermoelectric materials are of interest for converting waste heat to electricity and could be useful in applications such as power generation. Currently bulk bismuth telluride (Bi2Te3) is the most commonly used materials for refrigeration and waste heat recovery. However, theoretical calculation predicts that the performance can be dramatically improved by confining the dimensions of this material.
Electrodeposition provides a bottom-up technique compared to conventional coating methods, such as physical vapor deposition (PVD). It is of advantage in the efficient use of the starting material and can be used to plate curved surfaces and even inside of topologically demanding surfaces. The use of electrodeposition to fill nano-structures is also achievable, which is exploited in the Damascene process to grow 20 nm diameter Cu wires.
In electrochemical experiments water is the most commonly used solvent but its limitation includes narrow potential window, which is crucial in electrodeposition as water reduction will be a competing process as for metal reduction/deposition and provides introduces complexity to experiments. Here we employ an electrolyte system based on tetrabutylammoniumchlorometallate metal sources with compatible tetraalkyl halide supporting electrolytes in non-aqueous, weakly coordinating solvents, which provides the ability to deposit alloys with desired structures and properties.
In this work we report the deposition of Bi2Te3 films from dichloromethane. Bi2Te3 is a narrow band gap layered semi-conductor and it is demonstrated that the composition and structure of the BiTefilms can be controlled by tuning the electrochemical parameters, such as the electrolyte concentration and deposition potential.
孟令聪，男，英国南安普顿大学化学系研究员。2010和2012年在中南大学材料学院获得学士和硕士学位，2016年在英国华威大学获得理学博士学位。2016至今分别在英国华威大学从事博士后研究员和英国南安普顿大学担任研究员职务。其目前主要从事于基础电化学、高温高压电化学、电沉积功能材料等领域的研究工作。在国际知名期刊，如ACS Nano、J. Phys. Chem. C、Faraday Discussions等上发表十余篇代表性论文。
